Why You Can't Use Electronic Gadgets During Takeoff and Landing

Last Updated Dec 7, 2010 7:31 PM EST

Scientists possess hard (and hard-won) evidence about what can bring down an airliner. Lightning. Wind shear. Pilot error. But as far as we know, not a single crash has been attributed to a Kindle. Or a MacBook Air. Or any of the couple hundred cell phones that invariably ride coach during a typical flight.

And yet we can recite by heart the announcement that precedes every takeoff and landing: "At this time, please turn off and stow all electronic devices, including laptops, cell phones, and MP3 players."

Why does the FAA put the kibosh on these seemingly harmless gizmos whenever a plane slips -- or renews -- the surly bonds of earth? One reason: emissions. "There are still unknowns about the radio signals that portable electronic devices (PEDs) and cell phones give off," say FAA documents. "These signals, especially in large quantities and emitted over a long time, may unintentionally affect aircraft communications, navigation, flight control and electronic equipment."

Okay, fair enough, it's not worth nose-diving into the tarmac just because you're bored for 10 minutes. The thing is, you just know there's some noob in 12B who doesn't know how to put his Droid in Airplane mode. Or a grandma who thinks her Kindle is off when it's still pinging Amazon's servers. There's no way every single gadget gets powered down -- and yet thousands of flights take off and land safely every single day.

According to FAA spokesperson Alison Duquette, just because a PED hasn't been tied to an incident in the sky doesn't mean it can't happen. "We're always going to rule on the side of safety," she says. "Even if there's only the potential for a device to interfere with the aircraft's avionics, we're going to keep the rule in place."

But why only during takeoff and landing? Because most accidents occur during these critical phases of flight, Duquette says, and PEDs like laptops and MP3 players can distract passengers from more pressing matters -- like, say, finding the nearest door to escape a burning fuselage.

So while your iPod can't fool an altimeter into thinking it's at 500 feet when it's really at 50, it could prevent you from hearing important instructions during an emergency. Plus, it's a potentially deadly projectile, which is why airlines ask you to stow your PEDs, not just turn them off.

One final note to noobs, grandmas, and everyday rule-breakers: the regulation may seem silly, even unnecessary, but it's there for the sole purpose of your safety. Also, it's Federal law, so flout it at your own risk.

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Photo courtesy Flickr user swruler9284, CC 2.0
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